Tai, great; yuan, deep pool.
Tai means abundance. The Qi of meridian in the local part of this point is abundant as in a deep pool.
On the transverse crease of the wrist, in the depression on the radial side of the radial artery.
Cough, asthma, hemoptysis, pain in the chest and throat.
Perpendicularly 0.3-0.5 cun.